• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.15-24
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• 2013

Purpose: With the demand of SPECT/CT increasing, the interest in complex diagnostic information of CT is rising along with the expansion of various studies on potential performance value. But the study on reduction of exposure dose generated by CT is not being conducted enough. Therefore, in this study, the goal is to identify how much dose reduction exists when performing the extremity bone SPECT/CT using the flat-panel CT. Materials and Methods: The extremity bone SPECT/CT was performed with two equipments -BrightView XCT (Philips Healthcare, Cleveland, USA) and Brilliance 16 CT (Philips Healthcare, Cleveland, USA)-to identify the exposed dose and image quality resulted by changing scan parameter (mAs) applying for both equipment respectively. The noise value of image and spatial resolution were measured with AAPM CT phantom. Tube voltage (kVp) was fixed to 120 kVp, tube current (mAs) calculated at different mA (20, 30, 40, 50, 60, 70, 80) was applied to both equipments respectively. DLP (dose length product) were calculated at the same distance at respective mAs. Also, we acquired images and % contrast with NEMA IEC body phantom to confirm the effect on image. The output of statistics was analyzed by SPSS ver.18. Results: Regarding AAPM phantom, the noise decreased as the tube current (mAs) increased and flat-panel had less noise than Helical CT. This difference increased at lower dose exposure. As to the evaluation of spatial resolution, we can differentiate the space up to 0.75 mm with both equipments. With scan parameter (mA) growing, the value of DLP increased up to 54-216 mGy cm at flat-panel CT and up to 177-709 mGy cm at Helical CT. Regarding NEMA IEC body phantom, same sphere with varied parameter (mA) shows that similar results. Conclusion: There is no significant differences of image quality in both flat-panel and Helical CT when the scan parameter (mA) is changed respectively. Moreover, we can identify the reduction of exposure dose and confirm %contrast analysis value with maintaining image quality. Therefore, at the extremity bone SPECT/CT requiring high spital resolution without the wide ROI, the flat-panel CT is considered to be more useful and it expected to result in the similar image quality with lower exposure dose compared to Helical CT. Additionally, through this study, we expect to help the reduction of the unnecessary exposure dose.

• Journal of Life Science
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• v.21 no.8
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• pp.1163-1167
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• 2011

Excessive alcohol consumption causes various degenerative brain diseases including Alzheimer's disease and Parkinson's disease. Absorbed ethanol is metabolized to acetaldehyde and acetic acid by alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Acetaldehyde is well known as a toxicant through generation of reactive oxygen species (ROS). Therefore, ALDH2 activity may play important roles in the pathogenesis of alcohol-induced brain diseases. In this study, we demonstrated the effects of ALDH2 enzyme activity on lipid peroxidation in brain tissues and urine of mice exposed to ethanol for 8 weeks. Five male, 8-week old Aldh2 (+/+) and Aldh2 (-/-) mice (C57BL/6J strain) in each group were exposed to ethanol for 8 weeks (2 g/kg wt./day) using gavage, and those in the control group received 0.9% saline alone. Thiobarbituric acid reactive substances (TBARS) level, a marker for lipid peroxidation, was measured in whole brain tissue and urine by high performance liquid chromatography. As a result, chronic ethanol treatment did not show any statistical change on the TBARS level of brain tissue in both Aldh2 (+/+) mice and in Aldh2 (-/-) mice. However, following ethanol exposure for 8 weeks in Aldh2 (-/-) mice, the urinary TBARS levels were significantly increased to more than double compared to the pretreatment group. This result was not observed in Aldh2 (+/+) mice. These results suggest that although ALDH2 enzyme activity plays a role in the generation of ROS in the whole body, it does not seem to be important in the pathogenesis of alcohol induced degenerative brain diseases.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.616-623
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• 1996

Eum Yang Kwak, the aerial part of Epimedium koreanum, is widely used as a folk medicine for stimulant in man, tonic, and hypotensive purpose. The plant contains icariin (a specific flavonoid), magnoflorine (an alkaloid) and tannin, but their contents are not known until now. In this paper, a quantitative analysis method for them was developed. Determination of icariin and magnoflorine was successfully achived by high performance liquid chromatography equipped with a UV detector in the ranges of $0.1{\sim}0.4\;mg$ and $0.002{\sim}0.1\;mg\;per\;ml$ sample, respectively. Extraction of the plant was carried out with water or 50% ethanol using different decocting temperatures and times. Icariin was well extracted either by water ($100^{\circ}C$, 3hr) or 50% ethanol ($85^{\circ}C$, 1hr), and its content in the plant was measured to be 0.94%. On the other hand, magnoflorine was fully extracted by 50% ethanol ($85^{\circ}C$, 1hr), and its content was determined to be 0.16%. Therefore, decoction of the medicinal plant with water at $100^{\circ}C$ for 3hr turned out to be recommendable for the best extraction.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.10.1-10
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• 1982

The use of phonosurgery in the recent development of laryngomicrosurgery has enabled the restoration of a normal voice in respect to functional laryngeal surgery which in Korea in the past limited to simple removal of benign laryngeal tumor such as laryngeal polyp or nodules and cordal injection of $Teflon^{{\circledR}}$ for the treatment of recurrent nerve paralysis under the vision of suspension laryngoscopy. Performance of phonosurgery for the treatment of cord paralysis, mutational dysphonia, vocal cord atrophy, hyperkinetic dysphonia and sulcus vocalis is a happy event in the view point of development of phonosurgery in Korea. In this aspect thyroplasty to change the position and physical characteristics of the cord outside the glottis instead of the direct handling of the vocal cord through direct endoscopy is popular. Among the 4 types of thyroplasty, classified by Insshiki(1974), type I thyroplasty(1ateral compression of vocal cord) and type IV thyroplasty(lengthening of vocal cord) were effective in the treatment of unilateral vocal cord paralysis. Advantages of this operation are the fine adjustment of the degree of lateral compression under local anesthesia according to the phonation of the patient during operation and avoidance of dyspnea and intralaryngeal hemorrhage due to the manipulation outside the internal perichondrium of the thyroid cartilage. We did 7 cases of thyroplasty for the treatment of unilateral vocal cord paralysis in the 7 months from September 1981 to March 1982. Before the operation aerodynamic study, psychoacoustical evaluation, stroboscopy and sound spectrographic analysis were done. Two months after the operation the above procedures were performed again. Results of preoperative and postoperative examination were compared and the following results were obtained. 1) In the aerodynamic study, maximum phonation time increased to 158% of the preoperative value and the phonation quotient and the mean flow rate decreased to 58% and 54% of preoperative values. 2) The degree of hoarseness improved in the psychoacoustical evaluation and the glottic chink during phonation was decreased in the stroboscopic examiantion. 3) In the sound spectrographic analysis, periodicity was much restored and noise distribution decreased especially in the high frequency area.

• Journal of Korean society of Dental Hygiene
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• v.7 no.1
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• pp.73-89
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• 2007

The purpose of this study was to examine the reality of inservice education provided to members of Korean Dental Hygienists Association, the state of relevant academic conferences, and the perception of the members about inservice education and academic conference. It's basically meant to help boost their participation in inservice education and their satisfaction with it, and to show some of the right directions for that. The subjects in this study were dental hygienists who attended a symposium on July 1, 2006. After a survey was conducted, the answer sheets from 489 participants were analyzed, and the findings of the study were as follows: 1. General hospitals and university hospitals made up the largest group(91.4%) that gave a monthly leave of absence, and the second largest group was dental hospitals(75.4%), followed by dental clinics(58.3%) and public dental clinics(48.0%). The most common closing time in dental clinics and dental hospitals was 5 p.m., and that was 12 p.m. in general hospitals and university hospitals. The dental hygienists in public dental clinics didn't work on Saturdays. By type of workplace, treatment was the most common duty for the dental hygienists in dental clinics and dental hospitals to perform, and those who worked at general hospitals, university hospitals and public health clinics were in charge of extensive range of jobs. 2. The rates of the dental hygienists who took that education stood at 94.9% in public dental clinics, 78.7% in dental hospitals and 75.3% in dental clinics, general hospitals and university hospitals. Regarding how many marks they got on an yearly basis, those who got eight marks or more made up the largest group(55.6%), followed by four marks or more(11.8%), six marks or more(3.4%), and two marks or more(1.5%). As for the usefulness of inservice education for their job performance, the largest number of the dental hygienists(40.8%) found it to be helpful, and the second greatest group(37.5%) considered its effectiveness to be so-so. The third largest group(8.4%) found it to be of great use, and the fourth biggest group(4.2%) considered it to be of no service. The fifth biggest group(l.3%) thought it was absolutely useless. By type of workplace, the workers in dental clinics, dental hospitals, general hospitals and university hospitals wanted the most to learn how to take care of clinical work(acquisition of up-to-date technology), and those in public health clinics hoped the most to learn about public dental health. By type of workplace, the workers in dental clinics had their sight set on self-development the most, and the dental hygienists in dental hospitals, general hospitals, university hospitals and public health clinics were most in pursuit of acquiring new knowledge. By type of workplace, the specific given conditions at work were most singled out by the dental clinic workers as the reason, and the dental hospital employees pointed out time constraints the most. The dental hygienists in general hospitals and university hospitals cited time constraints and financial burden the most, and the public health clinic personnels mentioned inaccessibility of a place for inservice education as the reason. 3. The public health clinic workers participated in academic conferences the most(90.8%), followed by the general and university hospital personnels(68.8%), dental hospital employees(65.6%) and dental clinic workers(65.5%). By type of workplace, the public health clinic workers(73.5%) expressed the most satisfaction, followed by the general and university hospital employees(67.7%), dental clinic workers(62.3%) and dental hospital personnels(54.1%). By type of workplace, the employees of dental clinics, dental hospitals, general hospitals and university hospitals preferred Saturdays, and the public health clinic workers had a liking for weekdays. As for a favored place, hotels were most preferred, followed by university hospitals, general hospitals, college lecture rooms, district halls and local public institutions. Hotels were most favored regardless of the type of workplace. 4. Regarding outlook on inservice education, they had the highest opinion on the facilities and given conditions of lecture rooms($3.41{\pm}0.83$), followed by the professionalism of lecturers($3.34{\pm}0.83$), procedures of receipt and attendance confirmation($3.34{\pm}0.83$) and class size($3.13{\pm}0.89$). On the contrary, they took the most dismal view of the inaccessibility of a place of inservice education($2.08{\pm}0.92$), followed by limited opportunity and limited date for that education($2.51{\pm}0.99$), extra financial burden($2.53{\pm}1.18$) and high tuition fee($2.57{\pm}0.96$).

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.693-699
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• 2013

A simple, sensitive, and specific method for quantifying the nicotine content of synthetic favoring substances (SFS) was developed using high performance liquid chromatography (HPLC) with a photo-diode array detector (PDA). Nicotine was extracted from SFS samples by using an acid-base liquid-liquid extraction method with dichloromethane and distilled water. The nicotine content was quantified by HPLC/PDA (261.9 nm) with a $C_{18}$ column under a gradient of 10% acetonitrile with 20 mM ammonium formate (ammonia solution adjusted to pH 8.7) to 100% acetonitrile. The calibration curve, analyzed from concentration standards between 0.1 to 2 mg/L, presented linearity with a correlation coefficient ($r^2$)>0.9999. The limit of quantitation (LOQ) of nicotine in SFS was 0.4 mg/kg, and the average recoveries ranged from 76.4% to 96.3%. The repeatability of measurements, expressed as the coefficient of variation (CV%), ranged from 1.74 to 5.12%. This newly developed method for nicotine quantification in SFS can be considered an analytical method with an acceptable level of sensitivity and repeatability.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.1-10
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• 2003

The objects of this study were to develop a new strain which has resistance to fowl typhoid, high performance in laying, and producing brown shell eggs favored by domestic consumers. Several White Leghorn (WL) breeds known as possessing genetic resistance to fowl typhoid and several brown shell egg breeds such as susceptible to the disease were used to produce the controlled strains with cross mating between the strains within the breeds and the experimental strains with crossbreeding between the breeds. The crossbred strains were Chungnong(CN) 21, 22, 23, 24, 25 and 26. The controlled strains were ISA brown CC, Hyline brown CC and Lohman brown CC. The survival rates were 99.95% for chicks of age 0∼l7 weeks and 91% for adult chickens of age 18∼72 weeks. There was no difference in survival rate between the crossbred and the controlled strains. The means of age of lst egg laying were 147 to 148 days and no difference was observed between the crossbred and the controlled. The egg Production rates of a9e 18∼72 weeks were 83.76% far the crossbred strains and 77.82% for the controlled strains, which is significantly higher in the crossbred than controlled strains by 6%. The numbers of the hen housed egg Production of age 18∼72 weeks were 292.33 eggs for the crossbred strains and 271.31 eggs fur the controlled strains. The difference of 21 eggs more produced by the crossbred than by the controlled was statistically significant. The mean egg weights of age 18∼72 weeks were 64.32g for the crossbred strains and 60.73g for the controlled strains, and the difference of 3.59g was statistically significant. The feed conversion rates during the age of 18 to 72 weeks were 2.297 for the crossbred strains and 2.454 for the controlled strains. The crossbreds were reduced feed consumption by 157g for 1kg of egg Production which was statistically significant. Haugh unit(H$.$u) at the age of 72 weeks were 82.20 for the crossbred strains and 77.82 for the controlled strains. The crossbred strains were superior quality by 4.38 H$.$u. There were no significant differences in the yolk color and the eggshell thickness between the crossbred strains and the controlled strains. The eggshell color of the crossbred strains was light brown which is the medium color of the white eggshell strains and the brown eggshell strains. The body weights at the ages of 8, 12, 18, 42 and 71 weeks were not different between the crossbred strains and the controlled strains.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.87-94
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• 2012

To compare monthly variations of phytoplankton biomass and community composition between in seawater and sediment of the Gomso Bay (tidal flat: approximately 75%), the photosynthetic pigments were analyzed by HPLC every month in 1999 and every two months in 2000. Ambient physical and chemical parameters (temperature, salinity, nutrients, dissolved oxygen, and chemical oxygen demand) were also examined to find the environmental factors controlling structure of phytoplankton community. The temporal and spatial variations of chlorophyll a concentration in seawater were correlated well with the magnitude of freshwater discharge from land. The biomass of microphytobenthos at the surface sediments was lower than that in other regions of the world and 2-3 times lower than phytoplankton biomass integrated in the seawater column. Based on the results of HPLC pigment analysis, fucoxanthin, a marker pigment of diatoms, was the most prominent pigment and highly correlated with chlorophyll a in seawater and sediment of the Gomso Bay. These results suggest that diatoms are the predominant phytoplankton in seawater and sediment of the Gomso Bay. However, the monthly variation of chlorophyll a concentration in seawater at the subtidal zone was not a good correlation with that in sediment of the Gomso Bay. Although pelagic plankton was identified in seawater by microscopic examination, benthic algal species were not found in the seawater. These results suggest that contribution from the suspended microphytobenthos in the tidal flat to the subtidal zone of the Gomso Bay may be low as a food source to the primary consumer in the upper water column of the subtidal zone. Further study needs to elucidate the vertical and horizontal transport magnitude of the suspended microphytobenthos in the tidal flat to the subtidal zone.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.124-134
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• 2005

To investigate the exposure effect of polynuclear aromatic hydrocarbons (PAHs), we measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and analyzed the relationship between urinary 1-OHP concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. The airborne PAHs was obtained during survey day, and urine were sampled at the end of shift. Personal information on age, body weight, height, eniployment duration, smoking habit, and alcohol consumption was obtained by a structured questionnaire. Airborne PAHs were analyzed by the gas chromatograph with mass selective detector. Urinary 1-OHP levels were analyzed by the high performance liquid chromatograph with ultraviolet wavelength detector. For statistical estimation, t-test, ${\chi}^2$-test, analysis of variance, correlation analysis, arid regression analysis were executed by SPSS/PC (Windows version 10). The mean of environmental total PAHs was $87.8{\pm}7.81{\mu}g/m^3$. The mean concentration ($526.5{\pm}2.85{\mu}g/m^3$) of workers in steel-pipe coating industries using coal tar enamel was the higher than that ($17.5{\pm}3.36{\mu}g/m^3$) of workers in paint manufacture industries using coal tar paint. The mean of urinary 1-OHP concentration ($51.63{\pm}3.144{\mu}\;mol/mol$ creatinine) of workers in steel-pipe coating industries was the higher than that ($2.33{\pm}4.709{\mu}\;mol/mol$ creatinine) of workers in paint manufacture industries. The mean of urinary 1-OHP concentration of smokers was the higher than that of non-smokers. There was significant correlation between the urinary concentration of 1-OHP and the environmental concentration of PAHs (r=O.S48, p<0.001), pyrene(r=0.859, p<0.001), and urinary cotinine (r=0.324, p<0.05). The regression equation between the urinary concentration of 1-OHP in ${\mu}g/g$ creatinine($C_{1-OHP}$) and airborne concentration of PAHs (or pyrene) in ${\mu}g/m^3$ ($C_{PAHs}$ or Cpyrene) is: Log ($C_{1-OHP}$)=-0.650+0.889×Log($C_{PAHs}$), where $R^2=0.694$ and n=38 for p<0.001.Log ($C_{1-OHP}$)=1.087+0.707${\times}$Log(Cpyrene), where $R^2=0.713$ and n=38 for p<0.001. From the results of stepwise multiple regression analysis about 1-OHP, significant independents were total PAHs and urinary cotinine (adjusted $R^2=0.743$, p<0.001). In this study, there were significant correlation between the urinary concentration of 1-OHP and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking.

• Journal of the Korean Society of School Health
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• v.12 no.2
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• pp.295-303
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• 1999

The purpose of this study was to evaluate the effect of systemic oral health education on the improvement of knowledge levels and patient hygiene performance(PHP) for elementary school students. The randomly selected 1st and 5th grade students in a public elementary school of Taegu city were divided by education group(118 students) and non-education group(122 students). The oral health education lesson was systematically held on the education group once a month for 4 months. The questionnaire queried all the subjects about their knowledge and attitudes before and after oral health education, and PHP was also tested at the same time. Corresponding p-values were significantly considered at values less than 0.05. The obtained results were as follows: Due to the oral health education lesson, the education group of both 1st and 5th grade students came to have a higher knowledge level than the non-education group. There was high improvement of items such as toothbrushing time, toothbrushing method, cause of dental caries, treatment after tooth damage, and tongue-brushing. Therefore, these items should be educated to all the elementary school students. By increaseing the knowledge level of oral health after education, the PHP index in the education group was significantly decreased in comparison to the non-education group and hence the capability of oral health management improved. From the above results, a systematically and periodically oral health education system for elementary school students can improve the knowledge level and capability of oral health management. Further study will be required to develop an easy and acceptable systemic oral health education program for elementary schools.